A more thorough explanation:

Attorney work product refers to documents and other things that are created by or for a party or their representative in preparation for litigation. This means that lawyers can create materials that help them prepare for a case, and these materials are generally protected from being disclosed to the other side.

There are two types of attorney work product:

• Opinion work product: This includes the mental impressions, conclusions, opinions, and legal theories of an attorney. For example, an email from a lawyer to their client discussing legal research and trial strategy would be considered opinion work product. This type of work product is usually given more protection than ordinary work product and is almost never subject to discovery.
• Ordinary work product: This includes documents or facts that are outside of the attorney's mental impressions. For example, a bank statement would be considered ordinary work product. This type of work product is generally protected under attorney work product privilege, but it may be subject to discovery in certain circumstances.

Attorney work product is generally protected under attorney work product privilege, which means that it cannot be disclosed to the other side in litigation. However, this privilege may be overcome or waived in certain circumstances.

Imagine that a lawyer is preparing for a trial and creates a document that outlines their legal strategy. This document would be considered opinion work product because it includes the lawyer's mental impressions and legal theories. As a result, it would be protected from being disclosed to the other side.

On the other hand, imagine that the lawyer also collects bank statements as part of their preparation for the trial. These bank statements would be considered ordinary work product because they are outside of the lawyer's mental impressions. While they would still be protected under attorney work product privilege, they may be subject to discovery in certain circumstances.